<template>
  <div id="root">
    <div class="todo-container">
      <div class="todo-wrap">
        <MyHeader :addTodo="addTodo" />
        <!-- MyHeader传递参数给App -->
        <MyList
          :todos="todos"
          :checkTodo="checkTodo"
          :deleteTodo="deleteTodo"
        />
        <MyFooter
          :todos="todos"
          :checkAllTodo="checkAllTodo"
          :clearAllTodo="clearAllTodo"
        />
      </div>
    </div>
  </div>
</template>

<script>
import MyHeader from "./components/MyHeader";
import MyList from "./components/MyList";
import MyFooter from "./components/MyFooter.vue";

export default {
  name: "App",
  components: { MyHeader, MyList, MyFooter },
  data() {
    return {
      // 数据在app中，所以方法也在app中
      //由于todos是MyHeader组件和MyFooter组件都在使用，所以放在App中（状态提升）
      todos: JSON.parse(localStorage.getItem("todos")) || [],
    };
  },

  methods: {
    //添加一个todo
    addTodo(todoObj) {
      this.todos.unshift(todoObj);
    },
    //勾选或取消勾选
    checkTodo(id) {
      this.todos.forEach((todo) => {
        //遍历找对应选项取反
        if (todo.id === id) todo.done = !todo.done;
      });
      // 组件间通信
    },
    //删除一个todo
    deleteTodo(id) {
      // 过滤留下要的，flter不改变原数组
      this.todos = this.todos.filter((todo) => todo.id !== id);
    },

    //全选or取消全选
    checkAllTodo(done) {
      this.todos.forEach((todo) => {
        todo.done = done;
      });
    },
    //清除所有已经完成的todo
    clearAllTodo() {
      this.todos = this.todos.filter((todo) => {
        return !todo.done;
      });
    },
  },
  watch: {
    todos: {
      handler(value) {
        localStorage.setItem("todos", JSON.stringify(value));
      },
    },
  },
};
</script>

<style>
/*base*/
body {
  background: #fff;
}
.btn {
  display: inline-block;
  padding: 4px 12px;
  margin-bottom: 0;
  font-size: 14px;
  line-height: 20px;
  text-align: center;
  vertical-align: middle;
  cursor: pointer;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2),
    0 1px 2px rgba(0, 0, 0, 0.05);
  border-radius: 4px;
}
.btn-danger {
  color: #fff;
  background-color: #da4f49;
  border: 1px solid #bd362f;
}
.btn-danger:hover {
  color: #fff;
  background-color: #bd362f;
}
.btn:focus {
  outline: none;
}
.todo-container {
  width: 600px;
  margin: 0 auto;
}
.todo-container .todo-wrap {
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 5px;
}
</style>
